Certificate chain inspector
Read a certificate chain: who each certificate names, its key and extensions, its fingerprints, and whether each one was issued by the next.
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What the inspector checks
For each pair of certificates, the inspector checks that the names chain, that the key identifiers agree, that the issuer is a certificate authority allowed to sign certificates, and that the signature verifies with the issuer's key. It checks RSA, ECDSA P-256 and P-384, and Ed25519 signatures; others, such as SHA-1 signatures on old roots, are described but not checked. It does not check revocation or your trust store, which decide whether a verifier accepts the root.